Refugee from Dead Machine 2: Have GrRectBlurEffect use Linear filtering (rather than Nearest

src/effects/SkBlurMask.cpp

Index: src/effects/SkBlurMask.cpp
diff --git a/src/effects/SkBlurMask.cpp b/src/effects/SkBlurMask.cpp
index d22881aa9e126551ea6d2addfb36452302e24ee2..eb02c9d44be121d4cacc60ca3c70b0a59c130838 100644
--- a/src/effects/SkBlurMask.cpp
+++ b/src/effects/SkBlurMask.cpp
@@ -680,7 +680,7 @@ static float gaussianIntegral(float x) {
 uint8_t* SkBlurMask::ComputeBlurProfile(SkScalar sigma) {
     int size = SkScalarCeilToInt(6*sigma);
 
-    int center = size >> 1;
+    float center = 0.5f * size;
     uint8_t* profile = new uint8_t[size];
 
     float invr = 1.f/(2*sigma);